Eduardo Guilhon on "Error accessing a post, appearing like RSS"

When the alteration permanent links it asks to change the HTACCESS, this is the default.

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /blog2/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /blog2/index.php [L]
</IfModule>

Was modified for testing, but still the error occurs.
The Stranger is the "Feed" that appears is not related to selected post, and often appears the same feed for all posts clicked.